Although the likelihood of completion of a full course of isoniazid (INH) therapy is low in the population of subjects referred to tuberculosis clinics from short-term correctional facilities, we hypothesize that patients who keep an initial appointment are likely to complete a course of therapy. This study will review the outcome of patients referred for preventive therapy to the City of Hartford TB clinic from short-term correctional facilities and determine if it can be predicted which patients are likely to complete a course of therapy.